1. Field
This disclosure relates generally to integrated circuits, and more specifically, to integrated circuits with MOSFET transistors in which the gates are shaped.
2. Related Art
Circuit designs are based on the electrical characteristics of the elements being used in the particular circuit design. In the case of transistors, one of the important characteristics is the amount of current flowing for a given condition. This can be considered the effective width to length ratio of the gate. Due to process and lithography variables, the amount of current, or effective width to length ratio, varies from one transistor to another especially from wafer to wafer but can also be true on the same wafer or even the same integrated circuit. Such variation in effective width to length ratio makes circuit design more difficult. Reduction in such effective width to length ratio variation can result in the design of a circuit that has improved performance such as increased speed of operation, increased reliability of operation, and reduced power consumption. Of course there is continuing efforts to improve the manufacturing processes including lithography, but with improvements in these come reductions in transistor size which in turn has the effect of retaining the effective width to length variations.
Thus there is a continuing need for improvements in controlling the effective width to length ratio variation.